This invention relates to an operating device for an electric circuit breaker that is powered by a closing spring and, more particularly, relates to means for manually slowclosing the circuit breaker while the closing spring is disabled, or "gagged," in its charged condition.
The present invention is especially, though not exclusively, suited for use with the spring-actuated circuit breaker operating device disclosed and claimed in copending application Ser. No. 702,328-Barkan, filed July 2, 1976, and assigned to the assignee of the present invention. That operating device comprises a closing spring, a rotatable spring-controller mounted for rotation between first and second dead-center positions with respect to the spring, and means for transmitting charging forces to the spring in response to rotation of the spring-controller in a forward direction toward said first dead-center position. The spring acts to discharge and thereby further rotate the spring-controller in a forward direction when the spring-controller has been forwardly rotated past said first dead-center position. But releasable stop means coacts with the spring-controller to block this further forward rotation of the spring-controller. When the stop means is released, the spring is permitted to rapidly discharge and continue further forward rotation of the spring-controller into said second dead-center position. This latter rotation of the spring-controller is used to close the circuit breaker.
For charging the spring after a closing operation, the spring-controller is forwardly rotated from its second to its first dead-center position by a motor-driven rotatable driving member coupled to the spring-controller through a cooperating pawl and abutment. Just before the above-described stop is encountered by the spring-controller, the pawl and abutment are uncoupled, thus preventing the parts from being damaged by the impact resulting from this encounter.
When it is desired to effect a slow-closing operation in this general type of operating device, the closing spring is "gagged" in its charged condition, the stop means released, and the spring controller is slowly rotated by manual means through its usual closing stroke. This is the general procedure that we use, but we cannot utilize the above-described pawl and abutment for effecting such slow rotation of the spring-controller because the pawl and abutment are then uncoupled, as above described. It is, of course, possible to recouple the pawl and abutment to permit their use for such slow rotation of the spring controller. But such recoupling would involve structural complications and also complicated procedures that would have to be carefully followed to avoid damage to the operating device.